31316391 has 12 divisors (see below), whose sum is σ = 45359080. Its totient is φ = 20820240.

The previous prime is 31316387. The next prime is 31316413. The reversal of 31316391 is 19361313.

It is not a de Polignac number, because 31316391 - 2² = 31316387 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31316321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1180 + ... + 8001.

Almost surely, 2^31316391 is an apocalyptic number.

31316391 is a deficient number, since it is larger than the sum of its proper divisors (14042689).

31316391 is a wasteful number, since it uses less digits than its factorization.

31316391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9566 (or 9563 counting only the distinct ones).

The product of its digits is 1458, while the sum is 27.

The square root of 31316391 is about 5596.1049847193. The cubic root of 31316391 is about 315.2031644780.

The spelling of 31316391 in words is "thirty-one million, three hundred sixteen thousand, three hundred ninety-one".